Iron alloy



Patented Sept. 17, 1929 UNITED STATES PATENT OFFICE JAMES A. PAnsoNs, an, or DAYTON, omo, ASSIGNOB r THE nuamox oomm,

11m,v A conrom'rron on NEW Yonx IRON ALLOY No Drawing.

The invention relates to iron alloys, and is in part a continuation of my application, Serial. No. 240,929. It has for its objects the provision of an improved alloy of the iron silicon class, having high acid resisting qualities, which is tougher and more resistant to impact than those heretofore produced, which gives a denser casting, tree from gas inclusion or voids, and which, in general, has a wider field of service and greater reliability than alloys of this class heretofore developed.

I have found that alloys of iron and silicon, in which the silicon content ranges from 9 to per cent, and which are relatively weak and brittle and subject to fracture on impact and sudden change in temperature, may be greatly improved bythe use of certain of the carbide forming metals in connection with 20 carbon and by the use of nickel or cobalt.

By the use of these elements properly proportioned, I have found that strength of the alloy may be doubled and its acid resisting qualities increased five or six times. The use of the carbide forming metals in conjunction with the carbon provides the necessary amount of combined carbon to give the alloy its high corrosion resisting quality. Without such elements, when sand castings are made from high silicon iron alloys, all the carbon in the casting is in the form of graphite, and there is present substantially no combined carbon. Further, such graphite is in the form of flakes. By the addition of cobalt or nickel, the flakes are changed to nodules, which results in a large increase in the tensile strength of the casting. The amount of nickel or cobalt added must, however, be limited for two reasons. First,:nickel in amounts not be sufficient carbon left unprecipitated in.

over 1.5 percent materially reduces the acid.

desirable to introduce more of these elements; I

Application filed January 1.0, 1929. serial No. 331,103.

the alloy to combine with the carbide forming metals.

The carbide forming metals, which I have found suitable to add to the alloy are tungsten, vanadium and molybdenum, the elements being stated in the order of their affinity fpr carbon, the tungsten and vanadium being more suitable for this reason than the molybdenum. It will be understood that the three elements may be used in the alloy indi-, idually or in combination. The nickel and cobalt may similarly be used in the alloy together or separately. The following is a specific exampleof proportions and elements giving the improved alloy:

29c:- cant Silicon -Nickel or cobalt or combinations thereof 1 Tungsten, vanadium, molybdenum or combinations thereof"; 2

Carbon 7 0.8

Iron Balance I -However, the'proportion may vary overa considerable range, while still retaining 1n the alloy in a large degree the improved characteristics as above set forth. These proportions may vary'in accordance with the following limits:

' Per cent Silicon 9 to20 Nickel or cobalt or combinations thereof 0.1120 3 Tungstun, vanadium, molybden-- um or combinations thereof 0. lto 10 Carbon s 0.1120 1. 5 Iron Balancev -9 to 20 per cent of silicon,from 1 to 3 per cent of nickel, 0.1 to 10 per cent of metal bel ging to the group tungsten, vanadium and 10 molybdenum, suflicient carbon to combine with such metal and the balance iron.

2. .An iron silicon alloy consisting of from 9 to 20 per cent of silicon, from 1 to 3 per cent 5 of nickel, 0.1 to per centnf metal belonging .to the group tungsten, vanadium and molybdenum, from 0.1 to 1.5 per cent of carbon, and the balance iron.

3. An iron silicon alloy consisting of from 10 9 to per cent of silicon, from 1 to 3 per cent of metal belonging to the group nickel and cobalt, 0.1 to 10. per cent of metal belonging to the grou tungsten, vanadium and molybdenum, su cient carbon to combine with such 1 last metal and the balance iron.

4;. An iron silicon alloy consisting of about 14' per cent silicon, about 1 per cent of metal belonging to the group nickel and cobalt, about 2 per cent of metal ,belongin to the 20 group tungsten, vanadium and moly denum, about 0.8 per cent carbon and the balance iron.

In testimony whereofJ have hereunto subscribed my name this 8th day of January,

1929. JAMES A. PARSQNS, JR. 

